Starbursts and black hole masses in X-shaped radio galaxies: Signatures of a merger event?

We present new spectroscopic identifications of 12 X-shaped radio galaxies and use the spectral data to derive starburst histories and masses of the nuclear supermassive black holes in these galaxies. The observations were done with the 2.1-m telescope of the Observatorio Astronómico Nacional at San...

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Detalles Bibliográficos
Autor: Vahram Chavushyan
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2012
País:México
Institución:Instituto Nacional de Astrofísica, Óptica y Electrónica
Repositorio:Repositorio Institucional del INAOE
Idioma:inglés
OAI Identifier:oai:inaoe.repositorioinstitucional.mx:1009/1938
Acceso en línea:http://inaoe.repositorioinstitucional.mx/jspui/handle/1009/1938
Access Level:acceso abierto
Palabra clave:info:eu-repo/classification/Inspec/Galaxies: kinematics and dynamics
info:eu-repo/classification/Inspéc/Galaxies: formation
info:eu-repo/classification/Inspec/Galaxies: nuclei
info:eu-repo/classification/Inspec/Black hole physics
info:eu-repo/classification/cti/1
info:eu-repo/classification/cti/21
Descripción
Sumario:We present new spectroscopic identifications of 12 X-shaped radio galaxies and use the spectral data to derive starburst histories and masses of the nuclear supermassive black holes in these galaxies. The observations were done with the 2.1-m telescope of the Observatorio Astronómico Nacional at San Pedro Mártir, México. The new spectroscopic results extend the sample of X-shaped radio galaxies studied with optical spectroscopy. We show that the combined sample of the X-shaped radio galaxies has statistically higher black-hole masses and older episodes of star formation than a control sample of canonical double-lobed radio sources with similar redshifts and luminosities. The data reveal enhanced star-formation activity in the X-shaped sample on the timescales expected in galactic mergers. We discuss the results obtained in the framework of the merger scenario.